DESCRIPTION (Taken from the application):Tibial fractures are the most common long bone fractures. Surgeons agree that intramedullary nails are the implant of choice when surgery is indicated. However, the decision to, ream or enlargen the intirarnedullary canal prior to nail insertion remains controversial. Proponents believe that reaming increases cortical bow blood flow increases the stability of the fracture fixation, and provides autogenous bone graft at the fracture site. Opponents believe that reaming damages the endosteal blood supply and threatens fracture healing. We, therefore, propose a randomized trial of reamed vs nonreamed intramedulary insertion in 900 patients with dosed or open tibial shaft fractures. Eligible patients receive 1) reaming of the intramedullary canal prior to insertion of an intramedullary nail or 2) insertion of an intramedullary nail without prior reaming of the intramedullary canal. Surgeons will follow a strict protocol in managing patients in both groups. The protocol will include proscription to re-operation prior to six rnonths. The rate of re-operations aimed at improving fracture healing (bone grafting, nail exchange or removal, soft tissue coverage procedures) will be determined at 6 months, 9 months and one year. Secondary outcomes will Include return to work, functional status and health-related quality of life. The large size of the trial will reveal a more reliable and precise estimate of the true effect of both treatments. The results from this trial will be useful in guiding clinical practice.